MIDI:

There is a huge archive at
Utrecht University, the Netherlands, which contains lots of MIDI files which can be
downloaded and played on any system that supports MIDI. It also has lots of documentation about
MIDI and several MIDI programs for different platforms.
MidiJeff
has a collection of original songs, and there's a new archive at
Maple.nis.net
(which is often busy). A list of
Music Industry Contacts
is available.